T1 Terminator muzzle brakes are designed for .223 to 300 Winchester Magnums on barrels up to 17mm diameter
The T1 Dimensions are, 17.2mm, 0.677” diameter,  50mm, 1.96” long, 35-40 grams, 1.23-1.41 ozs
The T1 standard threads are,7/16 x 28 for Kimbers & ½ x 28,
The standard through hole is for a .224 & requires opening up to 0.025-0.030″ over calibre size if used on larger calibres up to a maximum of 30 cal.
The T1 doesn’t have a top or bottom, has flats for a spanner so they can be easily fitted by the Gunsmith. Ports are 90 degrees to the ground to reduce disturbance. The ports are angled back away from the shooter to minimise shooter discomfort and maximise performance.
It is recommended the rear of the brake be tapered down to the muzzle diameter when fitting.
The T1 Terminator with factory 7mm Rem Mag above it & factory 308 below it

The T1 Terminator with factory 7mm Rem Mag above it & factory 308 below it

A T1 Terminator on a Kimber Mountain Ascent.

A T1 Terminator on a Kimber Mountain Ascent.

T1 Terminator on a Weatherby Ultra Light.

T1 Terminator on a Weatherby Ultra Light.